How is drawdown in a well defined?

Drawdown in a well is defined as the difference in elevation between the static water level, which is the level of water in the well when it is not being pumped, and the surface of the cone of depression that forms when water is drawn from the well. The cone of depression is created as groundwater is removed during pumping, resulting in a lowering of the water level around the well. This definition is essential for monitoring the water table and understanding how groundwater resources are being affected by extraction activities. Evaluating drawdown is critical for assessing the sustainability of water supplies and managing the impacts on surrounding wells and ecosystems.

The other options do not accurately represent the concept of drawdown. The increase in water level during precipitation pertains to natural water level variations rather than changes due to pumping. Relationships between monitoring wells and the amount of water used during a specific period are not direct measurements of drawdown; rather, they pertain to different aspects of groundwater management and monitoring.